Oxygen-rich chemotherapyviamodified Abraxane to inhibit the growth and metastasis of triple-negative breast cancer

Oxygen-rich chemotherapyviaMnO₂modified Abraxane® for inhibiting growth and metastasis of triple negative breast cancer.

Neoadjuvant Therapy with Weekly Nanoparticle Albumin-Bound Paclitaxel for Luminal Early Breast Cancer Patients: Results from the NABRAX Study (GEICAM/2011-02), a Multicenter, Non-Randomized, Phase II Trial, with a Companion Biomarker Analysis

BACKGROUND

Nanoparticle albumin-bound paclitaxel (nab-Paclitaxel) is an alternative to standard taxanes for breast cancer (BC) treatment. We evaluated nab-Paclitaxel efficacy as neoadjuvant treatment for early estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) disease.

MATERIALS AND METHODS

Women with ER+, HER2-, stage II-III BC were treated preoperatively with four cycles of weekly nab-Paclitaxel (150 mg/m2), 3 weeks on and 1 week off. We hypothesized that poor pathological response rate (residual cancer burden [RCB] III; Symmans criteria) would be ≤16%.

RESULTS

Eighty-one patients with a median age of 47 years were treated; 64.2% were premenopausal, and 69% of tumors were stage II. Residual cancer burden III rate was 28.4% (95% confidence interval [CI]: 18.6%-38.2%), RCB 0+I (good response) rate was 24.7% (95% CI: 15.3%-34.1%) and RCB 0 (complete response) rate was 7.4% (95% CI: 1.7%-13.1%). Objective response rate by magnetic resonance imaging was 76.5% and rate of conversion to breast conserving surgery was 40.0%. The most frequent grade 3 and 4 toxicity was neutropenia (12.3% and 3.7% of patients, respectively), without any febrile neutropenia. Sensory neuropathy grade 2 and 3 were seen in 25.9% and 2.5% of patients, respectively. Tumor secreted protein, acidic, cysteine-rich (SPARC) overexpression was significantly associated with RCB 0 (odds ratio: 0.079; 95% CI: 0.009-0.689; p = .0216).

CONCLUSION

Despite failing to confirm an RCB III rate ≤16% in nab-Paclitaxel-treated patients, the RCB 0+I rate indicates a significant drug antitumor activity with low rates of grade 3-4 toxicity. Our exploratory biomarker analysis suggests a potential predictive role of complete response for SPARC. Confirmatory analyses are warranted, adapting dose and schedule to decrease peripheral neurotoxicity. (Trial registration: European Clinical Trials Database study number: 2011-004476-10; ClinicalTrials.gov: NCT01565499).

IMPLICATIONS FOR PRACTICE

The pathological response rate (residual cancer burden [RCB]; Symmans criteria) of nanoparticle albumin-bound paclitaxel administered as neoadjuvant treatment for early estrogen receptor-positive, human epidermal growth factor receptor 2-negative disease was evaluated. Whereas poor response (RCB III) was 24.7%, similar to that for docetaxel, good response (RCB 0+I) reached 23.0%, far superior to the 13% for docetaxel, while keeping toxicity low. Exploratory biomarker analysis suggests secreted protein, acidic, cysteine-rich overexpression in tumor cells as a potential predictor of complete response (RCB 0). Findings point to an encouraging single-agent neoadjuvant treatment with low toxicity, which warrants future research and development.

De-escalating and escalating treatments for early-stage breast cancer: the St. Gallen International Expert Consensus Conference on the Primary Therapy of Early Breast Cancer 2017

The 15th St. Gallen International Breast Cancer Conference 2017 in Vienna, Austria reviewed substantial new evidence on loco-regional and systemic therapies for early breast cancer. Treatments were assessed in light of their intensity, duration and side-effects, seeking where appropriate to escalate or de-escalate therapies based on likely benefits as predicted by tumor stage and tumor biology. The Panel favored several interventions that may reduce surgical morbidity, including acceptance of 2 mm margins for DCIS, the resection of residual cancer (but not baseline extent of cancer) in women undergoing neoadjuvant therapy, acceptance of sentinel node biopsy following neoadjuvant treatment of many patients, and the preference for neoadjuvant therapy in HER2 positive and triple-negative, stage II and III breast cancer. The Panel favored escalating radiation therapy with regional nodal irradiation in high-risk patients, while encouraging omission of boost in low-risk patients. The Panel endorsed gene expression signatures that permit avoidance of chemotherapy in many patients with ER positive breast cancer. For women with higher risk tumors, the Panel escalated recommendations for adjuvant endocrine treatment to include ovarian suppression in premenopausal women, and extended therapy for postmenopausal women. However, low-risk patients can avoid these treatments. Finally, the Panel recommended bisphosphonate use in postmenopausal women to prevent breast cancer recurrence. The Panel recognized that recommendations are not intended for all patients, but rather to address the clinical needs of the majority of common presentations. Individualization of adjuvant therapy means adjusting to the tumor characteristics, patient comorbidities and preferences, and managing constraints of treatment cost and access that may affect care in both the developed and developing world.

Emerging therapies for breast cancer

HER2 and CDK4/6 are undoubted two most important biological targets for breast cancer. Anti-HER2 treatments enhance objective response and progression-free survival/disease-free survival as well as overall survival. Three CDK4/6 inhibitors consistently improve objective response and progression-free survival; however, overall survival data are waited. Optimization of chemotherapy and endocrine strategies remains an unmet need. Check point inhibitor-based immunotherapy combined with chemotherapy is a promising field, especially for triple-negative breast cancer.

Efficacy and safety of nab-paclitaxel 125 mg/m2 and nab-paclitaxel 150 mg/m2 compared to paclitaxel in early high-risk breast cancer. Results from the neoadjuvant randomized GeparSepto study (GBG 69)

PURPOSE

The GeparSepto study demonstrated that the use of nab-paclitaxel instead of paclitaxel prior to anthracycline-based chemotherapy could lead to a significantly increased pCR rate, especially in the triple negative subpopulation. We report efficacy and safety for patients treated with two different doses of nab-paclitaxel in comparison to weekly solvent-formulated paclitaxel.

METHODS

Patients were treated for 12 weeks with either intravenous nab-paclitaxel 150 mg/m² (nP150) weekly, after study amendment 125 mg/m² (nP125) weekly or solvent-based paclitaxel 80 mg/m² (P80) weekly followed by epirubicin 90 mg/m² and cyclophosphamide 600 mg/m² on day 1 for four 3-week cycles.

RESULTS

229 patients received nP150, 377 nP125. Baseline characteristics were fairly balanced between these two sequential cohorts as well as compared to 601 patients receiving P80 except for hormone receptor status, HER2 status, and Ki67. Taxane treatment was discontinued in 26.8% (nP150), 16.6% (nP125), and 13.3% of (P80) patients, respectively. Median relative total dose intensity (mRTDI) based on 125 mg/m² for nP was 103% with nP150, 95% with nP125, 99% with P80 before and 98% with P80 after the amendment. PSN grade 3-4 was observed in 14.5% of patients with nP150, 8.1% of patients with nP125 (p = 0.018), and 2.7% of patients with P80. Overall pCR before the amendment was 33.6% after nP150 and 23.5% after P80 (OR 1.65 [95% CI 1.10-2.50]; p = 0.022); pCR after the amendment was 41.4% after nP125, and 32.4% after P80 (1.48 [95% CI 1.10-1.99]; p = 0.013).

CONCLUSIONS

Nab-paclitaxel 125 mg/m² was associated with a better safety profile and compliance without compromising the efficacy compared to nab-paclitaxel 150 mg/m².

ASCO 2016: highlights in breast cancer

At the 2016 ASCO Annual Meeting, several pertinent studies in the field of breast cancer were presented. MA17.R was the first randomized phase III trial to evaluate the prolongation of adjuvant aromatase-inhibitor (AI) therapy from 5 to 10 years; while a significant reduction of disease-free survival events was observed in the extended treatment group, the absolute difference was relatively small and longer endocrine therapy resulted in a higher fracture rate. A combined analysis of three North American trials emphasized the superiority of anthracycline containing adjuvant chemotherapy regimens compared with docetaxel/cyclophosphamide (TC), while the PANTHER trial investigated dose-dense tailored adjuvant treatment. In metastatic breast cancer, the main interest was on cyclin-dependent kinase (CDK) 4/6 inhibitors. In PALOMA-2, the addition of palbociclib to letrozole prolonged progression-free survival (PFS) from 14.5 to 24.8 months resulting in the longest PFS data ever reported in the first-line setting. A subgroup analysis of premenopausal patients accrued to PALOMA-3 indicated that in this patient subset, ovarian function suppression plus fulvestrant and palbociclib yielded results comparable to the postmenopausal population. ESR1 mutations were another focus of interest as these activating mutations in the gene coding for the estrogen receptor alpha apparently evolve under the selection pressure of AI therapy.